NO. 3587 OSTRACODS — HOBBS 3 



submarginal setae as in male although somewhat more abundant 

 anteriorly and posteriorly. Amiculum and J-shaped rod absent but 

 posterodorsal area with papilla projecting into cuplike cavity con- 

 taining material resembling that composing J-shaped rod of members 

 of genus Dactylocy there. 



Measurements (in millimeters). — 



hololype 

 number of specimens 

 length (range) 0.49 



average 

 height (range) 0.27 



average 



Type-locality. — Roadside ditch at Acerdale, 0.4 mile from junction 

 of Great Bridge and Indian River, Princess Anne County, Vu'ginia. 

 Specimens removed from collection of crayfishes dug from burrows. 



Disposition of types.— The holotypic male, the allotypic female, 

 and a dissected male paratype are deposited in the United States 

 National Museum, 113472, 113473, 113474, respectively. Para types 

 are in the collections of Mr. C. W. Hart, Jr., and in the joint collec- 

 tion of Miss Margaret Walton and the author. 



Range. — In addition to the type-locality, 0. ivaltonae is known 

 from the following: (1) a roadside ditch across from Stumpy Lake 

 on State Rte. 605, Virginia Beach, Princess Anne Co., Va.; (2) Lands- 

 town Road off Princess Anne Road, Virginia Beach, Princess Anne 

 Co., Va.; (3) roadside ditch near Great Bridge, Norfolk Co., Va.; (4) 

 Lyells, Rte. 202, Northumberland Co., Va.; (5) 2.5 mi. north of 

 Davidsonville, Kings Branch at Sands Road, Ann Arundel Co., Md.; 

 (6) 9.3 mi. east of Lyells, Rte. 202, Northumberland Co., Va.; (7) 

 6.4 mi. east of West Point on St. Rte. 14, King and Queen Co., Va.; 

 (8) 9.5 mi. north of Surry Court House, Surry Co., Va. 



Hosts. — In the type-locality 0. ivaltonae was found on Procam- 

 barus a. acutus (Gu-ard) and Camharus d. diogenes Girard. In all of 

 the other localities it was found on the latter. 



Relationships. — Ornithocythere waltonae seems to be most closely 

 alhed to Okriocythere cheia Hart (1964, p. 243) and to members of the 

 genus Geocythere. The chief resemblance is in the penis complex, 

 which consists of separated prostatic and spermatic elements. In aU 

 of these species the two elements, although distinct, are intimately 

 associated throughout the length of the prostatic element. Some- 

 what more distantly related are the members of the genera Asceto- 

 cythere and Plectocy there. It differs from aU of them in possessing 

 a beaklike prominence on the antrodistal extremity of the peniferum. 



OsTRACOD ASSOCIATES. — This specics was associated with Dactylo- 

 cythere jeanae, new species, in several of the localities cited above and 

 with Okriocythere cheia in the Landstown locality. 



